Avia S-99/CS-99

The Avia S-99 was a Czechoslovak copy of the Messerschmitt Bf.109G-6 with an Erla Haube canopy instead of the standard one.

Just after the war, as the German Luftwaffe had used Avia's factories and facilities to produce airplanes, the Bf.109 among them, the Czechoslovak had found that they had a large supply of blueprints, airframes and engines to keep producing their own version of the Bf.109G.

It was officially produced in two Avia's plants, both of them close to Prague as part of the corporative Automobilové zádovy (Automobile works), but they ran out of the German-made Daimler-Benz DB605 engine after many of them were destroyed when a warehouse exploded in Krásné Brezno.

The S-99 was the fighter variant, which was a direct copy of the Bf.109G-6 with some minor alterations like the Erla Haube canopy. The CS-99 on it's part was the training variant of it which was a direct copy of the Bf.109G-12. Twenty-one S-99 were completed plus twenty-three CS-99

Sources:
1. https://en.wikipedia.org/wiki/Avia_S-199
2. Salamander Books - The Complete Book of Fighters